In an operating room environment, anesthesia delivery systems are required to have backup power in the event of loss of AC mains power, while patient monitoring systems are not required to provide such backup power. When AC mains is lost, the clinician is put in an anxious situation since the anesthesia delivery system remains operational without any patient monitoring data. Clinicians would prefer to have the complete integrated anesthesia delivery and patient monitoring system remain powered when the AC mains is lost or interrupted.
FIG. 1 depicts a block diagram of an integrated anesthesia and patient monitoring system of the prior art. In this prior art model, an anesthesia machine 10 includes a power supply 14, a battery 16, a DC to DC converter 18 and an anesthesia machine load 20. An AC mains 12 power supply provides power to the anesthesia machine 10. A patient monitoring device 30 includes a power supply 34, a DC to DC converter 36 and a patient monitor load 38. An AC mains 32 power supply also powers the patient monitoring device 30.
In operation, when the AC main 12 power supply is present, the anesthesia machine 10 is powered by the AC main 12 power supply. When no AC main 12 power supply is available, or when the AC main 12 power supply falls below a functional operation level, the power supply 14 is disabled and the battery 16 powers the anesthesia machine load 20 through the DC to DC converter 18. The anesthesia machine 10 will receive power from the battery 16 until the battery 16 is depleted, or until the AC main 12 power is reestablished.
The patient monitoring device 30 will only operate if the AC main 32 is providing power to the power supply 34, thus powering the patient monitor load 38 through the DC to DC converter 36. Upon failure of the AC main 32 power supply, the patient monitoring device 30 will fail.
Current solutions to the interruption of operation of the patient monitoring device upon the loss of AC power include a patient monitoring power supply system with a battery that provides backup when AC mains is lost, and an anesthesia delivery system power supply that provides all power (when AC mains is available or the system is on battery) to the patient monitoring system such that the patient monitoring system does not have its own AC main supply. These solutions are oftentimes quite expensive.